chore(ci): revert automatically assign an author of a PR

[Yicong-Huang]

Reverts #3835. The added action technote-space/assign-author@v1 is not approved by apache.

[Copilot]

Pull Request Overview

This PR reverts a previously added GitHub Action that automatically assigns PR authors, as the technote-space/assign-author@v1 action is not approved by Apache. The change simplifies the workflow back to only handling PR labeling.

• Removes the unapproved technote-space/assign-author@v1 action
• Reverts workflow name from "Pull Request Automation" back to "Pull Request Labeler"
• Simplifies job name from pull_request_automation to labeler

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[aglinxinyuan]

LGTM!

[chenlica]

@Yicong-Huang I may not know some context. What's the reason the added action was not approved by Apache? Can we document it here?

[Yicong-Huang]

@aglinxinyuan please help answer the question

[aglinxinyuan]

@aglinxinyuan please help answer the question

ASF explains why only certain actions are permitted and provides a list of the allowed actions at the following link:
https://github.com/apache/infrastructure-actions